Zobrazeno 1 - 9
of 9
pro vyhledávání: '"Halvor Heier"'
Publikováno v:
Acta Ophthalmologica. 64:20-28
Various optical properties of the fundus camera may have important implications regarding the use of photographs for image size measurements. By scanning across retinal vessels with a microdensitometer the width and the intensity characteristics of b
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::637a300c25c5558d1988abfc0bc7f096
https://doi.org/10.1111/j.1755-3768.1986.tb00699.x
https://doi.org/10.1111/j.1755-3768.1986.tb00699.x
Autor:
Halvor Heier, Olaf Brinchmann-Hansen
Publikováno v:
Acta Ophthalmologica. 64:29-32
Changes in the caliber of retinal vessels may be of haemodynamic and morphological significance in various local and systemic vascular diseases. In this paper we present a theoretical study on the effects of structural density changes of the vessel w
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ff4d2323468de658ca4bfb60db7fbfe6
https://doi.org/10.1111/j.1755-3768.1986.tb00700.x
https://doi.org/10.1111/j.1755-3768.1986.tb00700.x
Theoretical relations between light streak characteristics and optical properties of retinal vessels
Autor:
Halvor Heier, Olaf Brinchmann-Hansen
Publikováno v:
Acta Ophthalmologica. 64:33-37
Due to the various surfaces of overlying structures, direct high magnification studies of retinal vessels in the living human eye is not yet possible. Our knowledge of microcirculatory mechanics of flow and morphological changes in vessel walls, is o
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::69129881068bf62d4f4e6640d78e40ed
https://doi.org/10.1111/j.1755-3768.1986.tb00701.x
https://doi.org/10.1111/j.1755-3768.1986.tb00701.x
Publikováno v:
Pure and Applied Optics: Journal of the European Optical Society Part A. 6:603-615
Scalar diffraction theories are often used to characterize optical imaging systems in terms of their scalar diffraction point-spread functions (PSFs). This works well at large f-numbers (low numerical apertures (NA)), since polarization effects can t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e5f0c87ef83e978d6ea1b42cd7e7ddf9
https://doi.org/10.1088/0963-9659/6/6/003
https://doi.org/10.1088/0963-9659/6/6/003
Autor:
Jakob J. Stamnes, Halvor Heier
Publikováno v:
SPIE Proceedings.
Two dterent methodsfor computing the ftracon OTF in complex optical systemsediscussed. The theoretical beis1 numerical aspects and computer imp''ementations e also dscussed. 1.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::49093d8922a262d98ffa14c77b070875
https://doi.org/10.1117/12.34887
https://doi.org/10.1117/12.34887
Autor:
Jakob J. Stamnes, Halvor Heier
Publikováno v:
Applied Optics. 37:3612
We describe an accurate technique for computing the diffraction point-spread function for optical systems. The approach is based on the combined method of ray tracing and diffraction, which implies that the computation is accomplished in a two-step p
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ec4418139620d18a26c956e7baecd86f
https://doi.org/10.1364/ao.37.003612
https://doi.org/10.1364/ao.37.003612
Autor:
Jakob J. Stamnes, Halvor Heier
Publikováno v:
Annual Meeting Optical Society of America.
Over the last ten years we have been developing a computer program for the efficient and accurate routine computation of the diffraction point spread function. The computation is accomplished in a two-step procedure in which one first employs ray tra
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::8e2d78d035ca545e8014dd6988315c3b
https://doi.org/10.1364/oam.1988.tum6
https://doi.org/10.1364/oam.1988.tum6
Autor:
Halvor Heier
Publikováno v:
Optica Acta: International Journal of Optics. 22:1044-1044
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::c3add8b0b60f9ac048b16b10bfa0048c
https://doi.org/10.1080/716099360
https://doi.org/10.1080/716099360
Publikováno v:
Applied Optics. 21:1628
The encircled energy is computed for large f/No. aberration-free annular aperture systems with linear obscuration ratios between 0.0 and 0.9. The computations are based on an algorithm due to Hopkins. The results are displayed graphically as contour
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8e44b3b81bf3dc00b43c6d9741abcc0a
https://doi.org/10.1364/ao.21.001628
https://doi.org/10.1364/ao.21.001628